Bulk Data Entry Specifies the value of PARAM,LOWRANK, which indicates the solution type for the faster Modal Frequency Response solution method invoked by PARAM,FASTFR and the FastFRS interface invoked by PARAM,FFRS.

Parameter Values Description
K4METH <-1.0, 0.0, 1.0>

Default = 1.0

(if PARAM, LOWRANK is not specified)

LOWRANK is set to 1.
LOWRANK is set to 0.
LOWRANK is determined based on the rank material damping matrix and number of fluid modes in the model.


  1. If both K4METH and LOWRANK are not specified, LOWRANK would be determined based on the material damping matrix and number of fluid modes.
  2. If LOWRANK is specified but K4METH is not specified, the value of LOWRANK would be used.
  3. If K4METH is specified, LOWRANK would be set according to K4METH.